Sleeping in on the weekend when you’re used to getting up early all week can affect your mood and increase the risk of depression, according to a new study.
Experts from Michigan Medicine, the University of Michigan’s academic medical center, used sleep and mood data from 21,000 young doctors taken over in a year.
An irregular sleep schedule can increase the risk of depression just as much as getting fewer hours of sleep in general or staying up late regularly, they found.
Sleeping in on a Sunday can even affect your mood on a Monday morning, they found, and make you just as cranky as you would be if you had stayed late on Sunday night.
Researchers have not studied the effect of mixed sleep schedules on the wider population, but believe it could apply to anyone with irregular sleep patterns.
Sleeping in on the weekend when you’re used to getting up early all week can affect your mood and increase your risk of depression, according to a new study.
The medical interns in this study were in their first year of residency training after medical school and went through long, intense workdays and irregular schedules, changing from day to day with no real structure.
These changes changed their ability to have a regular sleep schedule and made them the perfect subjects for a study of irregular sleep and mood patterns.
Data was collected by tracking their sleep and other activities via wrist devices and letting them record their mood on a smartphone app.
They also took quarterly tests for depression during the year-long study.
The new paper, published in the journal NPJ Digital Medicine, examines the impact this unusual mix of broken and irregular sleep has on the mind.
Those whose devices showed they had variable sleep schedules previously scored higher on standardized depression symptom questionnaires and had lower daily mood ratings, the study authors found.
Those who regularly stayed up late, or got the fewest hours of sleep, also scored higher on depression symptoms and lower on daily mood.
The findings add to what is already known about the link between sleep, daily mood and long-term risk of depression.
“The advanced wearable technology allows us to study the behavioral and physiological factors of mental health, including sleep, on a much larger scale and more accurately than before,” said Yu Fang, lead author of the new paper.
“Our findings are intended not only to guide self-management on sleep habits, but also to inform institutional planning structures,” added the research specialist.
Fang is part of the Intern Health Study team led by Srijan Sen, MD, Ph.D., which has been studying mood and depression risk in freshman medical residents for more than a decade.
The study collected an average of two weeks of data from before the doctors’ apprenticeship years began, and an average of four months of monitoring during the year.
Cathy Goldstein, MD, MS, associate professor of neurology and physician at Michigan Medicine’s Sleep Disorders Center, said wearable devices that estimate sleep are now used by millions of people around the world.
Experts from Michigan Medicine, the University of Michigan’s academic medical center, used sleep and mood data from 21,000 young doctors taken over in a year
This includes the Fitbit devices used in the study, other activity trackers, and smart watches such as the Apple Watch.
“With these devices, for the first time, we can effortlessly record sleep for long periods on behalf of the user,” says Goldstein.
“We still have questions about the accuracy of the sleep predictions consumer trackers make, although initial work suggests similar performance to clinical and research-grade actigraphy devices approved by the FDA.”
Sen said the new findings build on what his team’s work has already shown about high risk of depression among new doctors.
“These findings highlight sleep consistency as an underrated factor in depression and well-being,” he says.
“The work also underscores the potential of wearable devices for understanding important constructs relevant to health that we were previously unable to study on a large scale.”
The team notes that the relatively young group of people in the study – with an average age of 27, who earned both college and medical degrees – is not representative of the wider population.
However, because they all experience similar workloads and schedules, they are a good group to test hypotheses in and get a ‘broad’ picture of the broader population.
The researchers hope that other groups will study other populations, using similar devices and approaches, to see if the findings about variation in sleep schedules hold true for them and thus can be applied more widely to the population.
For example, Fang notes that the parents of young children may be another important group to study.
“I also wish my 1 year old could learn about these findings and only wake me up at 8:21 am every day,” she jokes.
The findings are published in the journal NPJ Digital Medicine.
Exposure to blue light from phones and computer screens ‘makes it harder to fall asleep’
Dhruvin Patel, a leading optometrist, is a specialist in the impact of blue light on eye health – that is, light produced by telephone and computer screens.
Blue light can make it more difficult to fall asleep and it affects eye health
Researchers say exposure to blue light can increase the risk of vision damage and make it more difficult to fall asleep.
Patel shared his tips for minimizing the impact of blue light while working from home or using screens.
1. Work at arm’s length from the screen
Fully extend your arm and work from a distance – looking from your eyes to the tip of your fingertips.
Use this as a minimum distance to reduce the load on your eyeballs.
20/20/20
Simply put, look away from the screen for a minimum of 20 seconds every 20 minutes at least 20 feet away.
This will help reset your visual systems and eyes during long periods of screen work.
3. Screen height
Height and height of your work screen can have a major impact on eye strain.
Research has shown that it is better to place the screen higher than the users viewing level – the center point should be 5-6 inches below the straight line of the users’ view.
This makes the space between the upper and lower eyelids more open, often resulting in drying of the eyes.
4. Lighting
Position the computer screen to avoid glare, especially from ceiling lights or windows.
Use blinds or curtains on windows, and replace the incandescent bulbs in desk lamps with lower wattage, lower intensity bulbs.
If there is no way to minimize glare from light sources, consider using an anti-glare filter.
5. Put a post-it note on your screen titled ‘BLINK’.
Normally we blink up to 20 times within a minute. This is automatically controlled by our central nervous system, so we are unaware of blinking.
On screens, this is actually reduced to 3-5 times per minute, which means that our tear films cannot be held and the eye does not stay lubricated.
A post-it note on your monitor that says “Blink” should help you consciously try to blink your eyes. It’s simple but absolutely works.
6) Consider your device
Usually the biggest, newest phone is best, but not for your eyes. An iPhone X is 20 percent brighter than an iPhone 6 and emits more blue light.
This is the difference from a 100 percent increase in exposure to harmful blue light!
7. Remember to turn off
I would recommend not using digital devices or artificial lighting after dark. If you’re like most people, you probably send that last-minute email or finish your favorite show on Netflix before going to bed.
Try to read a book or start that meditation you have promised yourself you will do in the new year.
Dhruvin Patel says you shouldn’t assume that ‘night mode’ or ‘blue tint’ on devices is enough to counteract the impact of blue light.
He said this ‘has been proven to not promote sleep compared to the normal output of a screen’ and so even when it is on you should still avoid the screen after dark if possible.
Patel founded the company Ocushield that makes screen protectors to filter out blue light based on his research into the impact of the light source.
Source: Dhruvin Patel (Ocushield)